Boring-machine.



No. 628,992 Patented .luly I 8, |899.

H. J. noBEnrs.

BBING MACHINE.

(Application filed Mar. 8, 1895. Renewed Dec. 19, 1898.)

2 Sheets-Sheet l.

om 9 olo wf u l. d, e t n e t a P .E .s Tm RH Ec BA 0M RG. J." .B Hw L 9nw 8 2 6 o.. N

(Application led Mar. 8, 1895, Renewed Dec. 19, 1898.)

2 Sheets-Sheet 2.

(No Model.)

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norma J. ROBERTS, or CHICAGO, ILLINOIS.

eoRlnie-arrotolaINE.4

SPECIFICATION for'riing part Of Letters Patent NO. 628,992, dated July18, 1899. i

Application filed March 8, 1895. Renewed December 1i), 1898. Serial No.699,753'. (No model.)

To all whom, it may concern:

Be it known that I, HOMER J. ROBERTS, of Chicago, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Boring-Machines; and I do 4hereby declare that the following is afull, clear, and exact description thereof, reference being had t-o theaccompanying drawings, and to the letters of reference marked thereon,which form a part'of this specification.

This invention relates to portable boringmachines adapted moreespecially for the convenient boring of holes in joists of a ceiling orfloor for the passage of concealedelecfric wires and other purposes.

The object of the invention is toprovide an improved apparatus of thecharacter de scribed which shall be positive in action, effective inoperation, durable in construction, and yet comparatively inexpensive.

Another object of the invention is to provide a device with mechanismfor rotating a drill or bit carrying spindle in which the operatingmechanism shall be within convenient reach of the operator standing uponthe door and which may be actuated by a vertical reciprocation ofparts--that is to say, by a sliding operating mechanism which may bevpulled down by hand and which may then be returned to its formerposition either by any suitable lifting mechanism, such as a spring, orby a second downward pull by the operator on a second part acting toreturn the first. This and other features of the invenwill be more fullyunderstood from the subjoined description of the accompanying drawingsand from the appended claims.

In said drawings, Figure 1 illustrates in side view the upper portion ofmy improved boring device. Fig. 2 represents a central longitudinalvertical sectional view of a portion of the same. Figs. 3 and drepresent transverse vertical sectional views taken, respectively, uponthe lines 3 3 and il 4 of Fig. 2, looking in the direction indicated bythe arrows. Fig. 5 is a side elevation of the entire ,device shown upona reduced scale, looking endwise upon the parts shown in Figs. 1 and 2;and Fig. is a similar view, somewhat enlarged7 of aportion of the same,looking in a direction at right angles to that of Fig. 5.

I Fig. 7is a View like that of Fig. `5, showing a modification embodyingadditional features.

rangement of the frame. Fig. 10 is a side View of the latter. Fig. 11 isa horizontal transverse sectional view ofthe same, upon an enlargedscale, taken upon the line 11 11 of Fig. 9 and looking in the directionindicated bythe arrows. Fig. 12 isa View similarto Fig. 1, showing amodified form of thev device. Fig. 13 is 'a central longitudinalverticalsectional View of the modification shown in Fig. l2. Fig. 14 isan end elevation of a portion of the frame shown in Fig. 12. Y Fig. 15is an end view of adrum, the section being taken on line 15 14E of Fig.12. Fig. 16 is an end view, partiallyin section, of a partof thewinding-drum to show the pawlsand-ratchet mechanism, being taken on line1616 of Fig. 12.

Referring now to Figs. 1 to 6 inclusi've,'A represents a standard of anysuitable construction, material, and strength, adapted to venient placeand provided at its upper portion with'an inwardly-projecting recess orsocket in which the spindle or stem A of the d rill-carrying frame A2mayenter and in which said stem A is firmly and adjustably secured bymeans of an adjusting-bolt CL', adapted to enter a suitablescrew-threaded aperture in the said frame-standard A and to engage or toimpinge upon the exterior of the spindle or stem A in a familiar manner.By this cnstruction the drill-carrying frame A2 may be adjusted withinthe frame-standard A as circumstances require. The frame A2 ispreferably of. metal and is provided at its ends with upturned arms orsupports a2, having suitable recesses in their ends adapted to re- Theshaft B is properly secured in position by means of caps CL3, suitablysecured to the upturned supports a2 by means of bolts and nuts, thebolts a" passing through suitable apertures in flanges a5, projectinglaterally from the said supports CL2 and caps a3, and being secured inposition by retaining-nuts a6. The forward end of the shaft B carriesthe in a modified form, showing the sliding ar` ceive and to constitutebearings for a shaft B.

Fig. S is a detail of one of the handle-grips, f

rest at its base a upon the oor or other con* ICO.

drill-holding spindle or chuck B, in the forward end of which the shankof the spindle or drill B2 is inserted.

Occupying the distance substantially between the adjacent faces of thesupports a2 and mounted upon the shaft B are two drums C C', eachprovided vat its two ends with an outwardly-extending annular iiange c.The two ends of a cable or rope D are secured at opposite ends of thedrum C, and said cable or rope winds upon said drum in oppositedicables.

rections, as clearly shown in Fig. 1, so that a downpull uponk oneportion of said cable will cause thel drum to revolve and that portionto unwind from the drum, while the other portion of the cable is beingsimultaneouslyA wound upon the drum, the drum revolving of course in thedirection of the cable which is beingunwoundbythepullthereon. Theends ofthe cable D' are similarly secured to the drum O, and said cable D' iswoundupon said drum in precisely the same manner as the cable D is woundupon the drum C, excepting that the sections thereof are wound indirections the reverse of the corresponding sections of the drum C. Thecable D', depending from the left-hand side of the drum C', when lookingat it as indicated by the arrow X in Fig. l, is trained across to theopposite side of the device and overa guide-pulley A3 and is suitablyspliced or secured, as jat d, to the righthand portion of the cable D,while that portion of the cable D depending on the righthand side of thedrum G' is similarly trained across and over the opposite side of thepulley A3 and suitably spliced or secured to the left-hand portion ofthe cable D, the points at which the several cables are spliced being atsuch distance from the drums C C as never to interfere with the windingof the The two depending portions of the cables D and D' areunited toform a continnous cable, which is trained around a pulley or guide A4,suitably mounted in the lower portion of the standard-frame A. Atconvenient places upon the cable are hand-grips d' d2, which grips areloosely mounted to slide upon guide-rods d3 d4, secured at oppositesides of the standard A'. From this construction it will readily beunderstood that the pulling down upon one handle or grip, as d, untilitshallbe in position (for example,shown in Fig. 5) will cause a downwardpull and an unwinding of the right-hand coils of both cables D D and theconsequent revolution toward the right and left of the drums C C',respectively, while at the same time the lefthand coils ofy the cableswill be wound up upon their respective drums. Similarly it will beobvious that the operation of the cables and the directions of rotationof the drums C C will be just the reverse of this when the operatortakes hold of the grip d'2 and pulls it down upon the side d4.

The drums C C/ are mounted loosely upon the shaft or spindle B, and inorder that each drum maybe engaged positively with said spindle or shaftB at certain times, so as to rotate the latter when the drum is rotatedin the proper direction, apawl-and-ratchet mechanism is employed, whichwill be presently described. The construction of this mechanism is suchthat each one of the drums may be alternately locked with the shaft Bwhen said drum is being operated or rotated toward the right, but isfree to rotate upon the shaft when turned in the opposite direc'- tion,whereby a continuous boring operation is maintained, although the drumsare alternately reversed. Provision is also made for reversing thepawl-and-ratchet engagement, whereby the drill maybe withdrawn, and,still further, for positively locking one of the drums to the shaft,whereby the power may be applied to the drill first inone direction andthen in the other, as in loosening the drill after having become wedgedor fastened in a knot or the-like. This pawl-and-ratchetmechanism is asfollows: Surrounding the shaft B is a sleeve E, provided with twoannular disks or flanges e e'. This sleeve E is located between theinner end heads c c2 of the drum C and C', respectively, which heads areposil the flange e', while the pawls e2 and e3 are fuly crumed to theiiange e. Vithin suitable apertures e5, extending in or through thesleeve E, are springs e, each of which. is adapted to engage and pressagainst a suitable projection upon each pawl e2 e3 e4, respectively, andthus normally cause the outward or engaging ends of the said pawls toenter the spaces between the several teeth of the ratchets C2 C3. InFigs. 3 and 4 the pawls e3 e4 are shownthus engaged, while the pawl e2is shown disengaged from the ratchet-teeth C2. The disengagement of thepawls is accomplished by means of sliding pins E, which are arrangedwithin and project through radial openings in the sleeve E andintheshaft B. There are three of these radial sliding pinsE, one for eachpawl, each of which engages at its outer end a suitable projection uponthe pawl, whereby when said pin is actuated by the means hereinafterdescribed, so as to be protruded at its outer end beyond the peripheryof the said sleeve E, it will pressagainst and lift up the engagingprojection of the pawl, compress the spring e of said pawl, and, turningsaid pawl upon its pivot or fulcr'um, lift its outer end out ofengagement with the ratchet-teeth, as clearly shown in said Fig. 4. Themeans for actuating said sliding pins E' is as follows: The shaft B isprovided with an axial recess b,extending throughout a portion ofitslength, which is adapted to receive a sliding arm F. For convenience ofconstruction said arm is IOS IIO

preferably a circular pin or rod of substantially the same diameter asthe diameter of the recess b, provided nearits inner end with a reducedportion or recess f, which is provided at each end with a rounded orbeveled shoulderff. The location of the reduced part fis such that whenthe sliding arm is moved one way or the other said part will bereciprocated between the ends of the pins E', and its length is greaterthan the distance between the remote sides of ltwo adjacent pins, butless than the distance between the pins farthest apart, so that theinner ends of either two adjacent pins may enter the reduced part orrecess at once when the sliding arm is in proper position, but not allthree of them. It will be obvious that with this construction thesliding arm may be shifted so that any desired single pawl is permittedto engage or so that the central pawl e3 and the one on either side ofit will engage the ratchet simultaneously. The rounded or beveledshoulders f act as cam-surfaces to project the pins E when the arm isshifted, and therefore act to throw the pawls out of engagement.

Means for shifting the arm F are provided in the form of a lever F',fulcrumed to the frame A2 at f2, one end of which is curved upwardly inposition to engage the outer end of the said sliding arm. A rod or cordf3 is attached to the other end of the lever, by means of which thelever may be oscillated to force the arm F inwardly against the actionof a coiled spring F2, interposed between the inner end of the arm andthe end of the bore or recess b.

From the above description it will readily be understood that theoperator may move the handle-pieces d' d2 continuously in alternatedirections and producea continuous rotary movement of the drill. Whenthe aperture is drilled through the floor-joist or drilled through tothe desired extent, the drill may be withdrawn from the aperture byreversing the ratchet mechanism, so as to rotate the drill in anopposite direction. This is accomplished by shifting the arm F, so as tothrow the pawls e3 and e4 out of engagement with their Vrespective drumsand to permit the pawl e2 to engage the ratchet of the drum C. This willobviously reverse the direction of rotation of the drill; but the latterwill be actuated intermittently, since only the drum C is provided witha pawl acting in this direction, and the drill. will therefore remainstationary during the rotation of said drum C in the right-handdirection, while the rotation of the drum C will have no effect whateveron the drill. Obviously the drum C' maybe provided with an additionalpawl acting in the same direction as the pawl e?, in which case therotation ofthe drill wo uld be continuous when reversed, the same aswhen driven in a right-handed direction. In some cases it may not benecessary to reverse the drill to withdraw' it, but it may be withdrawnby Vsimply pulling it out by hand force or by continuing the feedingrevolution of the drill with one hand while applying an outwardlypullingpressure on the implement with the other.

In Fig. 7 I have shown the same machine equipped with devices by whichit is adapted for the application of foot-power in conjunction with thehand grip hereinbefore described. is mounted to slide vertically up'onor within the lower part of the standard-frame and carries a pulley orroller G. A cord g, attached at one end to the frame-standard, as at g',is trained around said pulley and attached at its other end to one ofthe grips d or d2. As thus arranged, it will be obvious that pressureapplied on the treadle will aid in pulling down the handle or grip towhich the end of the cord is attached, and also that. the treadle willmove downward or have a travel less in extent than that of the grip. Inorder that a part of the power which may be applied by the foot in thismanner maybe ntilized to aid the other hand in pulling down the grip d2,a coiled contractive spring G2 is secured at one end to the frame, as atg2, and at its other attached to that one of the cables which will bewound up when the grip d is pulled down in such manner that the alsoshown for adjusting t-he lengths of the` cables. The upper part of thestandard Ais here shown as made to telescope within the lower partthereof, and these parts are held in adjusted relation by means of aset-screw g3, extending through the outer part and engaging the inner ina familiar manner.

The means herein shown for adj usting'the lengths of the cables'consistsin dividing the cables at the points where the grips are securedthereon, securing the ends of the lower section to the lower ends of thegrips iminovably and extending the ends of the upper cable-section downthrough holes formed lengthwise through the spool-shaped grips. In thelower end `of each grip is arranged a springpressed friction-clutch inthe form of a wedge d5, which engages the cable and prevents the gripfrom slipping downwardly therein. A knob d isprovided on the end of thewedge, by which the latter may be withdrawn to release the cable.-

In Figs. 9 to 16, inclusive, I have shown a modified form of myinvention which comprises but a single drill-actuating drum, but isprovided with an auxiliary or power-increasing drum, which may bebrought into action when required. As shown in these figures,

I-I designates the drill-actu ating drum, H the In this instance a stepor treadle Gk ICO lIO

auxiliary drumband H2 the main driving-cable. The upper part of thestandard, the yoke-frame, and bearings for the drums are substantiallylike those of the first-described iigures and are therefore similarlylettered herein and need not be more particularly described. The spindleor shaft is divided or formed in two sections I I', the adjacent ends ofwhich telescope together, as indicated clearly in the sectional figure,the length of each shaft-section between the bearings corresponding inlength to that of the drum thereon exclusive of the telescoping parts.The short section I is desirably secured immovably in the yoke-arm d2,(as herein shown by means of an inner shoulder and a clamping-n utthreaded on the outer end of the shaft,) so as to project therefrom as astud, although such construction is not necessary. The combined lengthof the, two drums is somewhat less than the length of the shaft-sectionsbetween the yoke-arms, so that the shorter drum Hl may be shiftedlongitudinally a short distance, and said drums are held normally awayfrom each other by means of a coiled spring J. The outer end of the drumH' is provided with recesses h h, adapted to engage posi tively with astud h', projecting from the inner-face of the arm a2, when the drum isadjacent to the latter, and the proximate ends of the drums are providedwith interlocking lugs h2, adapted to lock the drum so as to rotatetogether when the drum H is shifted u pv againstL the drum H. Abell-crank lever J', arranged and operated similarly to the lever F ofthe former machine, acts on the end of the drum I-I to force it intoengagement with the drum H against the action of the spring J. Theratchet mechanism in the present instance comprises a disk K, securedrigidly upon the shaft I and provided with a-tlange 7.9, within which ismounted a spring-pressed pawl 7c', adapted to engage with a series ofratchet-notches formed in the periphery of an annular end iiange 4,forming a part of the drum H. The main cable H2 is in the presentinstance coiled about the forward end of the drum H, trained from thencedown and around a pulley Z, carried upon a treadle L, mounted to slidein the lower part of the frame in a manner similar to that of the formerdevice, and from thence carried upward and wound upon the auxiliary drumH. H3 is a second cable, one end of which is coiled about the rearwardor left-hand end of the drum H in a direction the reverse of that of thecoils of the cable H2 thereon and the other end of which is attached tothe upper end of a coiled contractile spring M, similar to the spring G2hereinbefore described. The lower end of this spring is suitably securedto a cross brace or bar of the standard-frame- Instead of the grips fld2 of first-described machine a trans- Versely-arranged handle-bar N isprovided,

ranged to engage and slide within suitable grooves formed in the innerfaces of the two side members of the standard -frame, said guides beingattached to and forming the guiding members of the treadle L, so thatthe handle-bar and treadle necessarily move to gether.

Arranged as above described it will be obvious that when the handle-barand treadle are downward the main cable H2 will be unwound from the drumH and ,at the same time the auxiliary cable H will be wound up thereonagainst the tension of the spring M, which, when the pressure isrelieved, will reverse the motion of drum, unwind the cable H3, wind upthe cable H2, and return all the parts to their normal position, itbeing understood that the drum I'l is meantime locked in the positionshown in the drawings, and is consequently without movement in eitherdirection, and that the cable H2 simply runs around the pulley on thetreadle. When, however, it is desired to increase the power `thusapplied at the expense of movement or number of revolutions of the drillproduced by a single reciprocation of the actuating devices, the drum H'is shifted up into engagement with the drum H, thereby releasing it fromengagement from the stud and permitting it to rotate. Inasmuch as thispermits the cable H2 to unwind from both drums when treadle isdepressed, it follows that if the drums were of equal diameter theywould be rotated but one-half as many times with the same stroke of thetreadle as in the former case,when one end of the cable was practicallyimmovably attached to the yoke-frame, and that the power is thereforeincreased in a like proportion.v In the present instance the diameter ofthe drum I-I is greater than that of the drum I, and consequently thepower is still further increased at a corresponding sacrifice ofmovement.

It will be understood that I do not wish to be limited to the details ofconstruction described herein ezcept as claimed, it being obvious thatthese may be varied considerably without departing from the spirit ofthe invention.

I claim as my inventionl l. A boring-machine for overhead boring,comprising a tool-carrying spindle, a drum rotatably mounted thereonhavingratchet engagement with the spindle, a standardframe of sufficientlength to rest at one end upon the working floor and extend above thereach of the operator at its other end, journal-bearings on the upperend of said stand* ard within which said spindle is mounted, a guideupon the lower part of the standard and an operating-cable having itstwo ends coiled upon the drum in opposite directions and itsintermediate portion trained about the guide, substantially as setforth.

2. A boring-machine for overhead boring comprising a tool-carryingspindle, a drum rotatably mounted thereon and having ratch- IOS IIO

ets adapted to act in opposite directions on the spindle, astandard-frame adapted to rest on the working floor and extend above thehead of the operator, a yoke-frame mounted on the standard-frame,provided with bear ings for the tool-carrying spindle, mechanism forshifting the several ratchets into and out of operativeposition, a partof which shifting mechanism is arranged to extend downwardly to a pointaccessible to the operator, and an operating-cable having its two endswound upon the drum and its intermediate portion trained around a guideon the lower part of the standard-frame,substantially as set forth.

3. A boring-machine for overhead boring comprising a tool-carrying spindle, two drums rotatably mounted on the spindle and each having ratchetengagcmentwith the spindle, a standard-frame of a length to rest at oneend upon the working floor and extend above the head of the operator atits other end, bearings on said upper end with which the spindle isengaged, and means for driving the spindle comprising two cable-sectionswound upon each drum in opposite directions and having dependingportions interconnected between the two drums in crossed relation,whereby the drums will be rotated in reverse directions simultaneouslyand one of the coils of each wound up at the same time its other coil isunwound, substantially as set forth.

4. A boring-machine for overhead boring, comprisingatool-carryingspindle,two drums rotatably mounted on the spindle andeach having ratchet engagement with the spindle, a standard-frame of alength to rest at one end upon the werking door and extend above thehead of the operator at its other end, bearings on said upper end withwhich the spindle is engaged, and means for driving the spindlecomprising two cable-sections wound upon each drum in oppositedirections and having depending portions interconnected between the twodrums in crossed relation whereby the drums Will be rotated in reversedirections simultaneously and one of the coils of each wound up at thesame time its other coil is unwound, said interconnected portion beingtrained around a guide on the lower part of the standard, substantiallyas set forth.

5. A boring-machine comprising a toolbarrying spindle,asupporting-frame'with which said spindle has revoluble connection, twodrums revolubly mounted upon said spindle, a pawhand-ratchet mechanismin each drum adapted to engage and actuate the spindle when the drum isrevolved in one direction, said pawlandfratchct mechanisms of theseveral drums being arranged to act in the same direction, a thirdratchet mechanism in one of said drums adapted to act in a direction thereverse of the other ratchet in the same drum, means for shifting saidpawls out of operative position, and au operating-cable wound upon cachdrum, substantially as set forth.

G. Abo1ing-1nacl1ine comprising a tool-cai`- rying spindle, asupportingframe in which said spindle is revolu bly mounted, two drumsrevolubly mounted upon the spindle, a pawland-ratchet mechanism foreachdrum adapted to engage and actuate the spindle with the drum, saidpawlsof the several drums being arranged to act in the same direction, athird pawl for one of the drums, arranged to act on the spin dlein adirection the reverse of the other pawl of said drum, means for shiftingsaid pawls out of operative positions, comprising a member movablelongitudinally within the drums and provided with camsurfaces adapted toforce said pawls out of engagement with the ratchets and operatingcableswound upon each drum, substantially as set forth.

7. Aboring-mael1ine comprising a tool-carrying spindle, asupporting-frame in which said spindle is revolubly mounted, two drumsrevolubly mounted upon the spindle, each provided with a series ofratchet-notches, a spring-pressed pawl for each drum, mounted upon theshaft, said pawls being arranged to act in the same direction, a thirdpawl mounted upon the shaft and adapted to engage the ratchet-notches ofone drum in a direction the reverse of the other pawl acting on vsaiddrum, means for moving said pawls out of operative engagement With theirseveral drums, eomprisinga recess extending longitudinally of thespindle, pins extending from the pawls through the shaft into saidrecess, an' arm, provided with cam-surfaces adapted to act on said pins,and arranged to slide Within said recess, and an actuating-cable wou ndupon each drum, substantially as set forth.

8. A boring-machine comprising a tool-carrying spindle, asupporting-frame in which said spindle is revolubly mounted, two drumsrevolubly mounted upon the spindle, each provided with a series ofratchet-notches, a springpressed pawl for each drum, mounted upon theshaft, said pawls being arranged to act in the same direction, a thirdpawlmounted upon the shaft and adapted to engage the ratchet-notches ofone drum in a direction the reverse of the other pawl acting on saiddrum, means for moving said pawls ont of operative engagement with theirseveral drums, comprising a recess extending Ylongitudinally of thespindle, pins extending from the pawls through the shaft into saidrecess, an arm,

said pins; and arranged to slide within said recess, a lever pivoted onthe frame and arranged to shift said arm longitudinally and anactuatingbable wound upon each drum, substantially as set forth.

9. Aboring-maehine comprising a toolcar rying spindle,a driving-drumoperatively connected therewith,asuppOrtingstandard-frame ed, adriving-cable having each of its ends wound upon the driving-drum andits interl mediate portion trained about a guide-pulley provided withcam-surfaces adapted to act onv upon which the spindle anddrum aremount- IOO IIO'

IZO

mounted on the standard-frame, a second pulley mounted uponavertically-sliding treadle arranged within the lower part of thestandard-frame,an auxiliary driving-cable attached at one end to frameabove the treadle, trained around the pulley of the latter and attachedto the main driving-cable, and a hand-gri p atltached to the cable andarranged to slide upon guides at each side of the standardframe,substantially as set forth.

10. A boring-machine comprising a toolcarrying spindle, a frame withinwhich said spindle is mounted and a change-speed driving mechanism forthe spindle comprising a drum operatively connected with the spindle,

' a second drum mounted to rotate concentrically with the former drum,an operating-ca ble having its opposite ends wound upon the respectivedrums, and means forlocking the second drum from rotation and also forlocking it so as to rotate with the other drum, substantially as setforth.

1l. A boring-machine comprising a toolcarrying spindle, a frame withinwhich said spindle is mounted and a change-speed driving mechanism forthe spindle comprising a drum mounted upon the spindle and operativelyconnected therewith, a second drum mounted upon the spindle adjacent tothe former, a spring interposed between said drums to force themnormally apart, an operating-cable having each end wound upon one of theseveral drums, said ends being Wound in the same direction, and meansfor locking said second drum to the frame and also for locking it torotate with the other drum, substantially as set forth.

l2. A boring-machine comprising a toolcarrying spindle, a frame withinwhich said spindle is mounted and a change-speed driving mechanism forthe spindle comprising a drum mounted upon the spindle and operativelyconnected therewith, a second drum mounted upon the spindle adjacent tothe former, a spring interposed between said drums to force themnormally apart, an operating-cable having each end wound upon one of theseveral drums, said ends being wound in the same direction, a secondcable wound upon one of said drums in a direction opposite that of thefirst cable, and a spring arranged to lact on said second cable toresist winding up of the latter, substantially as set forth.

13. A boring-machine for overhead boring, comprising a tool-carryingspindle, a drum rotatably mounted thereon; having ratchet engagementwith the spindle, a standardframe of a length to rest at one end uponthe working floor and extend above the reach of the operator at itsother end, journal-bearings With which said spindle has engagement atsaid upper end, a guide upon the lower part of the standard, anoperating-cable having its ends coiled upon the drum in oppositedirections and itsintermediate portion trained about the said guide, atreadle mounted to slide vertically upon the lower part of the standardand provided with a guide-pulley, and an auxiliary cable secured at oneend to a part of the standard trained thence around the treadle-pulleyand secured at its other end to a part of the main operating-cable,substantially as set forth.

In testimony that I claim the foregoing as my invention I affix mysignature in presence of two witnesses.

HOMER J. ROBERTS.

l/Vitnesses: p

TAYLOR E. BROWN, ALBERT H. GRAVES.

